Scientists discover a new feature that distinguishes modern humans from Neanderthals

SKOLKOVO INSTITUTE OF SCIENCE AND TECHNOLOGY (SKOLTECH)

Research News

 

IMAGE: SCIENTISTS DISCOVER A NEW FEATURE THAT DISTINGUISHES MODERN HUMANS FROM NEANDERTHALS view more 

CREDIT: PAVEL ODINEV / SKOLTECH

Skoltech scientists and their colleagues from Germany and the United States have analyzed the metabolomes of humans, chimpanzees, and macaques in muscle, kidney, and three different brain regions. The team discovered that the modern human genome undergoes mutation which makes the adenylosuccinate lyase enzyme less stable, leading to a decrease in purine synthesis. This mutation did not occur in Neanderthals, so the scientists believe that it affected metabolism in brain tissues and thereby strongly contributed to modern humans evolving into a separate species. The research was published in the journal eLife.

The predecessors of modern humans split from their closest evolutionary relatives, Neanderthals and Denisovans, about 600,000 years ago, while the evolutionary divergence between our ancestors and those of modern chimpanzees dates as far back as 65 million years ago. Evolutionary biologists are after the particular genetic features that distinguish modern humans from their ancestors and may give a clue as to why humans are what they are.

Researchers from the Skoltech Center for Neurobiology and Brain Restoration (CNBR) led by Professor Philipp Khaitovich and their colleagues from the Max Planck Institutes in Leipzig, Dresden and Cologne and the University of Denver studied metabolic differences in the brain, kidney and muscle of humans, chimpanzees, and macaques.

The research supervisor was a renowned evolutionary biologist, Professor Svante Pääbo, who earlier on had discovered the Denisovan and led the Neanderthal Genome Project.

The team looked at an interesting human mutation that leads to amino acid substitution in adenylosuccinate lyase, an enzyme involved in the synthesis of purine inside DNA. This substitution reduces the enzyme's activity and stability, which results in a lower concentration of purines in the human brain. The team showed that the new mutation is typical for humans only and does not appear in other primates or Neanderthals. The researchers proved that this mutation is indeed the reason for the metabolic peculiarities in humans by introducing it into the mouse genome. The mice subjected to mutation produced fewer purines, whereas an ancestral gene, when introduced into human cells, led to apparent metabolic changes.

"Although a powerful tool for scientists, the decoded human genome, unfortunately, cannot account for all the phenotypic differences between humans. The study of the metabolic composition of tissues can give clues about why functional changes occur in humans. I am delighted that we have succeeded in predicting the metabolic characteristics of modern humans and validated our hypotheses on mouse and cell models, even though we did not have 'live Neanderthals' to work on," says lead author and Skoltech PhD student Vita Stepanova.

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Forensic archaeologists begin to recover Spanish Civil War missing bodies

CRANFIELD UNIVERSITY

Research News

 

IMAGE: THE MISSING FACES OF THOSE WHOSE BODIES THE TEAM ARE TRYING TO FIND. view more 

CREDIT: GEMA ORTIZ IGLESIAS

Forensic archaeologists and anthropologists from Cranfield University have started to recover the bodies of victims executed by the Franco regime at the end of the Spanish Civil War during an excavation in the Ciudad Real region of Spain.

The team from Cranfield is working with partners from the University Complutense of Madrid (UCM) and social anthropologists from Mapas de Memoria (Maps of Memory) to search for, exhume and identify those executed and buried in the civil cemetery at Almagro between 1939 and 1940.

Several bodies with gunshot wounds to the head, personal effects and parts of clothing have already been recovered and in total the team are searching for 26 people in this excavation which is focused on a separate area of the graveyard that has been closed for decades.

Families of victims have been found in the hope of identifying relatives through DNA analysis and returning the human remains for proper burial.

This exhumation is part of a number of recoveries from the Spanish Civil War which are currently being investigated in Spain. Since 2000, over 7,000 victims have been recovered.

Dr Nicholas Márquez-Grant, Senior Lecturer in Forensic Anthropology at Cranfield Forensic Institute (CFI), who is leading the excavation, said: "This excavation is particularly complex due to the number of victims and subsequent burials in the cemetery during the postwar period. Recovery of the bodies is carried out layer by layer and is only the start of the process to identify and bring dignity to the deceased and help to provide closure and peace to their families."

José Barrios, whose great uncle - also named José Barrios - was executed and buried at the site, said: "When the excavation started I did not feel much but when they found the first body, I saw the skull and the feet of an individual, I thought: we are here now, we are coming to find you."

The excavation period will last until the beginning of June and will be followed by a longer investigation involving anthropological analysis in the laboratory and DNA analysis until the end of 2021 to identify human remains recovered.

The first stage in the overall process was carried out by Maps of Memory to locate the graves through archival research and contact the families of victims through social networks and testimonies from neighbours.

Dr Jorge Moreno, director of Maps of Memory, a project of the National Distance Learning University (UNED), said: "Whilst archaeologists and forensic anthropologists work from the ground down, social anthropologists work from the ground up. Whilst scientists search for human remains, social anthropologists search for families, their histories and stories. Originally we had four families identified for this excavation and in ten days we now have 21 families and 21 stories. We find bodies on the one hand, and stories on the other that later connect."

A total of 11 pits have been identified for the excavation, and several pits have more than one individual in them. Cranfield team members also include graduates and alumni from CFI's Forensic Archaeology and Anthropology MSc.

Once remains are recovered, they are taken to the forensic anthropology laboratory at UCM to identify and determine the circumstances of the death of each of the individuals.

Dr Maria Benito Sanchez, director of the scientific team for the project from the School of Legal Medicine at UCM, said: "As forensic anthropology professionals we have the responsibility of putting our science to the service of the relatives who have been searching for their loved ones for a long time now. Since I started working on mass graves, there have been many rewards which I take with me, and all are for the relatives - they are the engine for this work."

Genetic analysis with samples from family members and bone samples recovered then follows and where checks are positive, family members are identified. Remains will then be passed to the families for burial or returned to the cemetery to be buried again if that isn't possible.

The wider Memory Maps project, which is funded by the Ciudad Real Provincial Council, has located 53 mass graves and named 3,457 people killed in the province of Ciudad Real by the Franco regime over the last ten years. So far the Almagro excavation is the largest mass grave opened in the province, although there are known to be others with hundreds of people buried in them.

CAPTION

Archaelogists and anthropologists from Cranfield University, University Complutense of Madrid (UCM) and Mapas de Memoria (Maps of Memory) in Almagro .

CREDIT

Cranfield Forensic Institute

CAPTION

An aerial view of the dig site in Almagro.

CREDIT

Cranfield Forensic Institute

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 THIRD WORLD USA

Dual impacts of extreme heat, ozone disproportionately hurt poorer areas

A frequent combination on hot days, high temperatures and ozone disproportionately affect low-income ZIP codes, researchers find

UNIVERSITY OF CALIFORNIA - SAN DIEGO

Research News

 

Scientists at UC San Diego, San Diego State University and colleagues find that extreme heat and elevated ozone levels, often jointly present during California summers, affect certain ZIP codes more than others.

Those areas across the state most adversely affected tend to be poorer areas with greater numbers of unemployed people and more car traffic. The science team based this finding on data about the elevated numbers of people sent to the hospital for pulmonary distress and respiratory infections in lower-income ZIP codes.

The study identified hotspots throughout the Central Valley, areas of San Diego County east of downtown San Diego, and places like San Bernardino, where Los Angeles basin smog is often trapped by surrounding mountain ranges, among others.

Results appear the week of May 24 in the journal Proceedings of the National Academy of Sciences. The Office of Environmental Health Hazard Assessment, a division of the California Environmental Protection Agency, funded the research.

"This information can be used to activate measures to protect populations in areas which we know will be at increased risk of experiencing a health burden from these co-occurring environmental events and maximize public health benefits," said study lead author Lara Schwarz, a graduate student who is in a joint doctoral program at San Diego State and the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego.

In places like California, these public health hazards are expected to appear in unison more frequently as the climate continues to warm and heat waves become more prevalent and long-lasting. The study could enable more targeted public health efforts because of its unprecedented consideration of two common hazards in tandem and its relatively high-resolution breakdown of where they are most likely to cause problems. Previous studies had tended only to evaluate city- or regional-level health trends.

"Understanding the health impacts of compounding environmental events such as extreme heat and various air pollutants like tropospheric ozone becomes a priority in a changing climate," said study co-author Tarik Benmarhnia, a climate change epidemiologist with appointments at UC San Diego's Scripps Institution of Oceanography and Herbert Wertheim School of Public Health and Human Longevity Science. "Such events are more frequent, intense and tend to co-occur, potentially creating synergistic effects on population health impacting the most vulnerable communities."

The work could inform early warning systems and prioritize resources more efficiently than at present, the researchers said.

Ozone, a gas and a variant molecular form of oxygen, is formed in the lower atmosphere by the reaction of various hydrocarbons to sunlight, especially during hot days. Car exhaust produces such hydrocarbons. Ozone can exacerbate asthma and other respiratory conditions among vulnerable people and is more prevalent in urban areas with more traffic.

Extreme heat can similarly affect respiratory health by itself or in combination with high ozone levels.

Schwarz's team notes that vulnerability to the excessive heat/ozone combination seems to be diminished in wealthier ZIP codes and correlated results with factors that include better access to healthcare, lower stress levels, and more exercise.

"When considering the ZIP code level, certain areas observed strong joint-effects," said the study authors. "A lower median income, higher percentage of unemployed residents and exposure to other air pollutants within a ZIP code drove stronger joint-effects; a higher percentage of commuters who walk/bicycle, a marker for neighborhood wealth, showed decreased effects."

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Besides Schwarz and Benmarhnia, authors include Kristen Hansen of the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego, Anna Alari of Sorbonne University in Paris, Sindana Ilango of the University of Washington, Nelson Bernal of the University of Brasilia in Brazil, Rupa Basu of the California Environmental Protection Agency, and Alexander Gershunov of Scripps Institution of Oceanography at UC San Diego.

New insights on animals in the African past

Researchers discover new peptide markers to expand identification of Africana bovid taxa

UNIVERSITY OF TENNESSEE AT KNOXVILLE

Research News

 

IMAGE: ANNEKE JANZEN view more 

CREDIT: UNIVERSITY OF TENNESSEE, KNOXVILLE

In order to understand foodways and subsistence strategies of humans in the past, as well as distributions of ancient animal species, it is critical for archaeologists to accurately identify animal taxa in archaeological sites. Many sites across sub-Saharan Africa have fragmented and poorly preserved animal bones, leaving the majority of specimens unidentifiable. Sub-Saharan Africa is also home to the greatest diversity of bovids on Earth, including African buffalo, wildebeest, eland, and duikers, as well as domestic sheep, goat, and cattle. The sheer number of osteologically similar animals in Africa presents a major challenge for identifying animal bones.

During the past decade, archaeologists have increasingly used a bone collagen peptide fingerprinting technique called Zooarchaeology by Mass Spectrometry (ZooMS) to identify ambiguous or unidentifiable bone fragments. However, the lack of complete reference peptide markers for African animals has hindered its application in Africa. In a new study, "Distinguishing African bovids using Zooarchaeology by Mass Spectrometry (ZooMS): New peptide markers and insights into Iron Age economies in Zambia," published in PLOS ONE, researchers present a complete set of confirmed ZooMS peptide markers for all groups of African bovids, revealing new opportunities for archaeologists to identify these species in archaeological sites.

"Our new reference dataset has the potential to revive research interest in, and add value to, assemblages previously considered too poorly preserved for traditional zooarchaeological analysis," said Anneke Janzen, assistant professor in the Department of Anthropology at the University of Tennessee, Knoxville, and lead author on the study.

Using these new peptide markers, Janzen and her team applied the ZooMS method to extremely fragmented animal bone assemblages from six Iron Age archaeological sites in Zambia and discovered the number of species present is greater than expected.

"With this new data, we discovered that Iron Age populations continued to hunt wild bovids, especially small duikers, in addition to relying on cattle-based pastoralism," Janzen said.

"Our research opens new opportunities for addressing questions of paleoenvironment, subsistence strategies, foodways, the spread of and development of herding economies in the African past," Janzen said.

CAPTION

A yellow backed duiker at the Knoxville Zoo.

CREDIT

University of Tennessee, Knoxville

New fishing tech may pose risks to fisheries, says study co-authored by UMass researcher

Scientists need to work closely with resource management agencies to assess impacts

UNIVERSITY OF MASSACHUSETTS AMHERST

Research News

 

IMAGE: ANDY DANYLCHUK RELEASING HIS CATCH. view more 

CREDIT: ANDREW BURR

AMHERST, Mass. - New developments in recreational fishing technology--from the use of aerial drones and social media scouting reports to advances in hook design--are creating challenges for fisheries management and effective policy making, according to a new study co-authored by University of Massachusetts Amherst researcher Andy Danylchuk.

With the opening of the spring fishing season, millions of recreational fishing aficionados across North America are dusting off their tackleboxes, fitting together their rods, and heading to the bait and tackle shop to purchase the latest in fish-catching gear. But what impact does all that new technology have on the fish themselves?

"There are still so many unknowns," says Andy Danylchuk, professor of fish conservation in the UMass Amherst department of environmental conservation, and co-author of a new paper that investigates the relationship between fishing technology and fish ecosystems. "There's more attention paid to products we use with our pets than to what we use to try to catch fish in our streams, lakes and oceans."

Fishing technology has come a long way since the days of hook and worm. Today one can buy battery-powered, artificial lures that wriggle like minnows and are slathered in fish-attracting scent. Underwater cameras and fish finders help anglers not only seek out their targets but also observe as fish either approach or reject the bait. Aerial drones scan for fish and even deliver lures to them. Social media helps pinpoint, in real time, what fish are biting where. Even the seemingly simple hook has been completely redesigned to better reel in the big one. And it's not as if recreational fishing in streams, lakes, and in the ocean is a niche-activity--it is the second most popular leisure activity in North America, falling just behind gardening.

"From improvements in finding and catching fish, to emulating their natural prey and accessing previously inaccessible waters, to anglers sharing their exploits with others, technology is completely changing all aspects of recreational fishing," says Steven Cooke, professor of fish ecology in Carleton University's department of biology and the study's lead author.

Without knowing what impact all this advanced technology has on the fish and their aquatic ecosystems, it has become difficult for fisheries managers to monitor the health of the fishery, and to ensure that the fishing experience is a positive one. "Recreational anglers have always been a strong voice for conservation," says Danylchuk. "If something changes and they are no longer catching fish, they're one of the first stakeholder groups to raise the alarm about possible environmental harms." It turns out that what's good for the fishing community is also good for the fish: more, and healthier fish means a more enjoyable, successful fishing experience.

What this means for the research and management community is that more attention needs to be paid to the effects of high-tech fishing equipment. "An important message here is that resource management agencies need to share their experiences and that scientists should more intensively study the impact of innovations in recreational fishing," write the study's authors. "If science can't keep up in terms of evaluating the impacts of technological innovation to help inform management and policy," says Danylchuk, "it can be really detrimental to the fish, which may ultimately mean fewer fish, and a worse fishing experience for anglers."

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Contacts: Andy Danylchuk, danylchuk@eco.umass.edu Daegan Miller, drmiller@um

Virus infection cycle revealed in dynamic detail

JOHN INNES CENTRE

Research News

 

IMAGE: VIRUS LIKE PARTICLES ARE MIMICS OF THE NUDAURELIA CAPENSIS OMEGA VIRUS A MODEL USED TO PROVIDE DYNAMIC DETAILS ABOUT THE PROCESS OF VIRAL MATURATION view more 

CREDIT: ROGER CASTELLS-GRAELLS

A critical process in the infection cycle of viruses has been revealed for the first time in dynamic detail using pioneering plant-based technology.

Evidence about the process of virus maturation revealed in the research could help us develop new methods for treating viral infections.

Maturation plays a critical role for all animal and bacterial viruses and is required to produce infectious virions or particles. Though the outlines of the process have been determined for many groups of viruses, detailed mechanistic studies have not been reported.

To provide the first detailed mechanistic study of maturation, Roger Castells-Graells, a rotation Ph.D. student working in Professor. George Lomonossoff's laboratory at the John Innes Centre infiltrated genetic material of the insect virus Nudaurelia capensis omega virus (N?V) into dwarf tobacco plants N.benthamiana.

This transient expression technique uses Virus Like Particles (VLPs) which are mimics of the authentic virus. The capsid or protein coat of the virus is produced by plant cells and the research team then analyses the material purified from infiltrated leaves.

The research demonstrated that maturation of procapsids - immature viral structures - can occur within plant cells to yield fully functional mature capsids. This has not been observed previously in the absence of a natural infection and is a new application for the transient expression system pioneered by Professor Lomonossoff at the John Innes Centre.

Comparative cryo-EM analysis of the structures of the procapsids and mature capsids revealed the large structural rearrangements both inside and between the protein subunits of the capsid that accompany maturation. These shape changes enable the chemical reactions that are necessary for the virus to infect the host.

Professor Lomonossoff, a group leader at the John Innes Centre, said: "Most structural studies of virus particles to date have given a static picture of the particles. By isolating particles from plants that are undergoing the process of maturation, we have managed to obtain a picture of the dynamics of an essential part of a virus infection cycle."

The present study, a collaboration involving scientists at the University of Leeds, in Brazil and the USA, as well as at the John Innes Centre, reveals details of the structures at the beginning and the end of the maturation process. What is now required is an analysis of intermediate steps to get a complete understanding of the dynamics.

This will enable the research team to determine the 3-D structures of intermediates in the maturation process to create a "movie."

"We have shown that maturation occurs over time within plant cells and that means we have discovered a valuable tool for studying virus maturation. We hope it will be of interest to potential collaborators and industry," said Professor Lomonossoff.

Plant-expressed virus-like particles reveal the intricate maturation process of a eukaryotic virus appears in Communications Biology

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Posts to Reddit forum "SuicideWatch"

spike in the early hours of Monday

morning

KING'S COLLEGE LONDON

Research News

 

Posts to Reddit forum "SuicideWatch" spike in the early hours of Monday morning

New research from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King's College London has found that people on a social media suicide support forum are most likely to post to the site during the early hours of Monday morning.

The study, which has been published in BMC Psychiatry, suggests that there is a clear variation in behaviour throughout the week and throughout the day. The researchers hope that this means that targeted support to at risk populations can be made more readily available to those most in need.

The researchers looked at the timings at which users of the Reddit forum "SuicideWatch" posted online. The forum is a moderated online community for individuals who are either at risk of, or know someone who is at risk of suicide.

The data, which was taken between 1st December 2008 and 31st August 2015, amounted to 90,518 posts. Over the course of a given week, posts to the forum were at their highest on Mondays between 02:00 and 05:00 in the morning. Posts trended downwards from Tuesday to Saturday. This was in stark contrast to data taken from the control group "AskReddit", a separate forum on the same site in which users can ask general questions of each other, which saw most content posted in the later hours of the day.

Dr Rina Dutta, the study's Primary Investigator from King's IoPPN said "Monday has often been identified as the day of the week which has the highest risk of someone taking their own life. From the data that we've studied, we can see a clear trend over weekly cycles that closely follows the suicide timing patterns reported in some earlier studies."

The timings of the posts suggest that active users are experiencing disturbances to their sleep, and may represent a potentially modifiable risk factor for suicidal thoughts and behaviours.

Dr Dutta said, "Extensive use of social media has been associated with disturbed sleep, anxiety, depression, and low self-esteem. Reducing the use of social media during the night hours might be an effective means of providing targeted psychological interventions in some individuals."

The researchers believe that using this data can be used to target at risk populations with greater levels of support.

"Given that we have a clear indication as to when at risk people are posting to this forum, it is challenging but certainly not implausible to envisage providing higher levels of moderation on Reddit during times of increased posting about suicidality. If developed in the right way, we might have the capacity to target otherwise unreachable populations to deliver suicide prevention messaging and interventions where and when they are needed most."

Ends

For further information please contact Patrick O'Brien, Senior Media Officer (Patrick.1.obrien@kcl.ac.uk)

About King's College London

King's College London is one of the top 10 UK universities in the world (QS World University Rankings, 2018/19) and among the oldest in England. King's has more than 31,000 students (including more than 12,800 postgraduates) from some 150 countries worldwide, and some 8,500 staff.

The Institute of Psychiatry, Psychology & Neuroscience (IoPPN) which is the premier centre for mental health and related neurosciences research in Europe. It produces more highly cited outputs (top 1% citations) on mental health than any other centre (SciVal 2019) and on this metric we have risen from 16th (2014) to 4th (2019) in the world for highly cited neuroscience outputs. World-leading research from the IoPPN has made, and continues to make, an impact on how we understand, prevent and treat mental illness and other conditions that affect the brain. https://www.kcl.ac.uk/ioppn @KingsIoPPN

 

Clean water and toilets for healthy shelters

TOHOKU UNIVERSITY

Research News

 

IMAGE: TRAINED MEMBERS OF THE ISHINOMAKI ZONE JOINT RELIEF TEAM CONDUCTED VISUAL ASSESSMENTS OF RESOURCE SUPPLIES AND INFRASTRUCTURE IN EVACUATION SHELTERS. view more 

CREDIT: HELIYON

Regular, standardized assessments of evacuation shelters can help keep people healthy following natural disasters, according to research published by Tohoku University scientists and colleagues in the journal Heliyon. The study found that a clean tap water supply and hygienic toilets were especially important for protecting evacuees from the spread of infectious diseases.

"A clean water supply and maintaining hygiene are important for reducing environmental health risks among victims of natural disasters," says Tadashi Ishii, who specializes in disaster medicine at Tohoku University. "But scientists have not yet established a strong evidence base that describes the relationship between damage in resource supplies and infrastructure on the one hand and disaster victims' health status on the other."

Ishii led the Ishinomaki Zone Joint Relief Team following the Great East Japan Earthquake of March 11, 2011. More than 15,000 people died and 2,500 went missing following the disaster, with some 500,000 evacuated to shelters across Japan. It took nearly a year before all shelters were shut down.

The team conducted regular visits to the shelters in order to assess resource availability, infrastructure, and the health status and needs of people residing in the shelters. Now, Ishii and his research team have analysed these 2011 records to evaluate the impacts of resource supply levels and infrastructure damage on the physical health of evacuees.

Their study included 28 mid- to large-sized shelters regularly assessed in the weeks following the earthquake. The study looked specifically at changes made to resources and infrastructure between days 14 and 25 after the earthquake.

The team found that inadequate clean tap water and toilets were insufficiently improved during the assessment period in about half the shelters. Clinical symptoms of common respiratory and gastrointestinal infections were more prevalent in shelters where these two resources had not improved. Shelters that were able to improve the supply of clean tap water and toilet hygiene witnessed significant reductions in the prevalence of gastrointestinal symptoms among evacuees.

"Our study demonstrated the difficulty of quickly collecting objective assessment data from evacuation shelters during the acute phase of a massive disaster," says Ishii. "It also shows the validity of quick visual assessments of resources by trained staff. Importantly, the study reveals the importance of rapidly restoring clean water supply and toilet hygiene in shelters to reduce environmental health risks among evacuees."

Ishii and his team next plan to develop easy, reliable and quick assessment tools for evaluating resource damage and health status in evacuation shelters. He also stresses the importance of collaborating with local governments to set up effective supply chains that can rapidly deploy clean water and hygienic rescue toilets in the aftermath of natural disasters.

CAPTION

Actual scene of quick visual assessment of the rescue toilet by the relief team member.

CREDIT

Tohoku University

Deep and extreme: Microbes thrive in transition

KING ABDULLAH UNIVERSITY OF SCIENCE & TECHNOLOGY (KAUST)

Research News

 

IMAGE: A RICH COMMUNITY OF PREVIOUSLY UNDESCRIBED MICROBES EXISTS IN THE TRANSITION LAYER BETWEEN THE DEEP WATER OF THE RED SEA AND THE SURFACE OF BRINE POOLS, SUCH AS THAT PICTURED... view more 

CREDIT: © CALADAN OCEANIC LLC

A diverse microbial community has adapted to an extremely salty environment deep in the Red Sea. The microbes, many unknown to science, occupy a one-meter-thick area overlying the Suakin Deep, an expansive 80-meter-deep brine lake, 2,771 meters below the central Red Sea. The chemical properties of this thin "brine-seawater interface," along with the composition of microbial communities, change surprisingly rapidly across a sharp gradient.

"Our study sheds light on how microorganisms in the Suakin Deep's brine-seawater interface make an oasis of life in the desert of the deep Red Sea," says microbial ecologist Daniele Daffonchio, who led the study. Daffonchio and his colleagues at KAUST, with collaborators in Germany and Spain, found that microbial cell densities are more than double in this interface than in normal deep Red Sea water and the brine below.

The Suakin Deep is one of around 25 deep brine lakes in the Red Sea. Few studies have analyzed the thin brine-seawater interface above it, and none have taken into account how its properties change from top to bottom.

Daffonchio's team used a sampler called a Niskin Rosette to analyze water every nine centimeters within this interface. This cylindrical apparatus holds 23 identical 90-centimeter-long 10-liter bottles, along with a detector that measures salinity, temperature and depth.

The sampler was deployed by KAUST's research vessel with the bottles open until the detector signaled that the apparatus had reached the Suakin Deep's brine-seawater interface. The bottles were then filled with interface water and remotely shut, and the apparatus then returned to the ship. This way, the water column in the bottles represented most of the water column in the interface. One-liter fractions of water, each corresponding to a different depth in the actual interface, were analyzed for their chemical and microbial contents.

The team found many types of microbial communities, which changed with variations in oxygen and salinity within the water column.

"Many of the microbes were new, with their closest relatives coming from hydrothermal vents at the bottom of the sea and from subsurface sediments," says environmental microbiologist Grégoire Michoud, the study's first author.

The team sequenced the genome of a microbe they called Candidatus Scalindua arabica, which was concentrated within a 20-centimeter-layer in the middle of the brine-seawater interface. The metabolic processes conducted by this and other microbes suggest this transition zone is a critical niche for nitrogen cycling.

Oceanic brine pools could be similar to extraterrestrial environments like the saline ocean that is expected to exist under the surface of Jupiter's satellite Europa. "Knowledge of the microbial networks in extreme Earth environments could help us hypothesize how lifeforms on extraterrestrial bodies thrive and function," explains Daffonchio. "These microbes could also harbor enzymes and other properties that could be useful in medical and biotechnology applications."

The team plans to continue analyzing other Red Sea brine pools and their brine-seawater interfaces to examine how different conditions affect microbial content.

Plasma jets reveal magnetic fields far, far away

Radio telescope images enable a new way to study magnetic fields in galaxy clusters millions of light years away

NAGOYA UNIVERSITY

Research News

 

IMAGE: A BLACK HOLE (MARKED BY THE RED X) AT THE CENTRE OF GALAXY MRC 0600-399 EMITS A JET OF PARTICLES THAT BENDS INTO A "DOUBLE-SCYTHE " T-SHAPE THAT FOLLOWS THE MAGNETIC... view more 

CREDIT: MODIFIED FROM CHIBUEZE, SAKEMI, OHMURA ET AL. (2021) NATURE FIG. 1(B)

For the first time, researchers have observed plasma jets interacting with magnetic fields in a massive galaxy cluster 600 million light years away, thanks to the help of radio telescopes and supercomputer simulations. The findings, published in the journal Nature, can help clarify how such galaxy clusters evolve.

Galaxy clusters can contain up to thousands of galaxies bound together by gravity. Abell 3376 is a huge cluster forming as a result of a violent collision between two sub-clusters of galaxies. Very little is known about the magnetic fields that exist within this and similar galaxy clusters.

"It is generally difficult to directly examine the structure of intracluster magnetic fields," says Nagoya University astrophysicist Tsutomu Takeuchi, who was involved in the research. "Our results clearly demonstrate how long-wavelength radio observations can help explore this interaction."

An international team of scientists have been using the MeerKAT radio telescope in the Northern Cape of South Africa to learn more about Abell 3376's huge magnetic fields. One of the telescope's very high-resolution images revealed something unexpected: plasma jets emitted by a supermassive black hole in the cluster bend to form a unique T-shape as they extend outwards for distances as far as 326,156 light years away. The black hole is in galaxy MRC 0600-399, which is near the centre of Abell 3376.

The team combined their MeerKAT radio telescope data with X-ray data from the European Space Agency's space telescope XXM-Newton to find that the plasma jet bend occurs at the boundary of the subcluster in which MRC 0600-399 exists.

"This told us that the plasma jets from MRC 0600-399 were interacting with something in the heated gas, called the intracluster medium, that exists between the galaxies within Abell 3376," explains Takeuchi.

To figure out what was happening, the team conducted 3D 'magnetohydrodynamic' simulations using the world's most powerful supercomputer in the field of astronomical calculations, ATERUI II, located at the National Astronomical Observatory of Japan.

The simulations showed that the jet streams emitted by MRC 0600-399's black hole eventually reach and interact with magnetic fields at the border of the galaxy subcluster. The jet stream compresses the magnetic field lines and moves along them, forming the characteristic T-shape.

"This is the first discovery of an interaction between cluster galaxy plasma jets and intracluster magnetic fields," says Takeuchi.

An international team has just begun construction of what is planned to be the world's largest radio telescope, called the Square Kilometre Array (SKA).

"New facilities like the SKA are expected to reveal the roles and origins of cosmic magnetism and even to help us understand how the universe evolved," says Takeuchi. "Our study is a good example of the power of radio observation, one of the last frontiers in astronomy."

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The study, "Jets from MRC 0600-399 bent by magnetic fields in the cluster Abell 3376," was published in the journal Nature on May 5, 2021, at https://www.nature.com/articles/s41586-021-03434-1.

About Nagoya University, Japan

Nagoya University has a history of about 150 years, with its roots in a temporary medical school and hospital established in 1871, and was formally instituted as the last Imperial University of Japan in 1939. Although modest in size compared to the largest universities in Japan, Nagoya University has been pursuing excellence since its founding. Six of the 18 Japanese Nobel Prize-winners since 2000 did all or part of their Nobel Prize-winning work at Nagoya University: four in Physics - Toshihide Maskawa and Makoto Kobayashi in 2008, and Isamu Akasaki and Hiroshi Amano in 2014; and two in Chemistry - Ryoji Noyori in 2001 and Osamu Shimomura in 2008. In mathematics, Shigefumi Mori did his Fields Medal-winning work at the University. A number of other important discoveries have also been made at the University, including the Okazaki DNA Fragments by Reiji and Tsuneko Okazaki in the 1960s; and depletion forces by Sho Asakura and Fumio Oosawa in 1954.

Website: http://en.nagoya-u.ac.jp/